First ovulation after childbirth: the effect of breast-feeding

Hormonal and natural contraceptives: a review on efficacy and risks of different methods for an informed choice

The debate about contraception has become increasingly important as more and more people seek safe and effective contraception. More than 1 billion women of reproductive age worldwide need a method of family planning, and wellbeing, socio-economic status, culture, religion and more influence the reasons why a woman may ask for contraception. Different contraceptive methods exist, ranging from 'natural methods' (fertility awareness-based methods - FABMs) to barrier methods and hormonal contraceptives (HCs). Each method works on a different principle, with different effectiveness.FABMs and HCs are usually pitted against each other, although it's difficult to really compare them. FABMs are a valid alternative for women who cannot or do not want to use hormone therapy, although they may have a high failure rate if not used appropriately and require specific training. HCs are commonly used to address various clinical situations, although concerns about their possible side effects are still widespread. However, many data show that the appropriate use of HC has a low rate of adverse events, mainly related to personal predisposition.The aim of this review is to summarize the information on the efficacy and safety of FABMs and HCs to help clinicians and women choose the best contraceptive method for their needs.

Time to Resumption of Menses, Spatial Distribution, and Predictors Among Post-partum Period Women in Ethiopia, Evidence From Ethiopian Demographic and Health Survey 2016 Data: Gompertz Inverse Gaussian Shared Frailty Model

Background

The timing of the resumption of post-partum menses is important for a woman who intends to avoid subsequent unintended pregnancy, and it has key implications on maternal, neonatal, and child health outcomes. Despite this, information is scant about the time to resumption of post-partum menses and predictors in Ethiopia. Therefore, this study aimed to determine the time it takes to start menses and spatial distribution among post-partum period women in Ethiopia and identify its predictors.

Methods

A secondary data analysis was conducted based on 2016 Ethiopian Demographic and Health Survey (EDHS). A total weighted sample of 6,489 post-partum women was included in the analysis. STATA 14 was used to weigh, clean, and analyze the data. The shared frailty model was applied since the EDHS data have a hierarchical nature. For checking the proportional hazard assumption, the Schenefold residual test, Log-Log plot, Kaplan–Meier, and predicted survival plot were applied. Akakie Information Criteria (AIC), Cox–Snell residual test, and deviance were used for checking model adequacy and for model comparison. Based on these, the Gompertz inverse Gaussian shared frailty model was the best-fitted model for this data. Variables with a p < 0.2 were considered for the multivariable Gompertz inverse Gaussian shared frailty model. Finally, the adjusted hazard ratio (AHR) with a 95% confidence interval (CI), and a p < 0.05 was reported to identify the significant predictors of time to the resumption of post-partum menses.

Results

The median survival time to post-partum menses resumption was 14.6 months. In this study, 51.90% [95% CI: 50.03, 53.76] of post-partum period women had resumed, and the risk of menses resumption was 1.17 times [AHR: 1.17; 95% CI: 1.03–1.33] higher among urban resident, 1.14 times [AHR: 1.14; 95% CI: 1.0–1.24] in women who had attended formal education, and 1.63 times [AHR: 1.63; 95% CI: 1.4–1.7] higher among women who used hormonal contraceptives. However, the risk of post-partum menses resumption was lower among 7–24 months breastfeeding women by 36% [AHR: 0.64; 95% CI: 0.5–0.76], women with child alive by 26% [AHR: 0.74; 95% CI: 0.6–0.85], and multiparous women by 27% [AHR: 0.73; 95% CI: 0.6–0.80].

Conclusion

Almost half of the participants had resumed post-partum menses, with the median survival timing of menses resumption at 14.5 months. Women residing in urban areas, who attended formal education, and using hormonal contraceptives have a shorter time to resume post-partum menses, whereas a woman with an alive child, breastfeeding practice, and multiple parity has a longer time to resume post-partum menses. Therefore, the healthcare providers and program managers should act on the resumption of post-partum menses through health education and promotion to cultivate the 14 months lag period identified by considering the significant factors.

Lactational Amenorrhea: Neuroendocrine Pathways Controlling Fertility and Bone Turnover

Lactation is a physiological state of hyperprolactinemia and associated amenorrhea. Despite the fact that exact mechanisms standing behind the hypothalamus-pituitary-ovarian axis during lactation are still not clear, a general overview of events leading to amenorrhea may be suggested. Suckling remains the most important stimulus maintaining suppressive effect on ovaries after pregnancy. Breastfeeding is accompanied by high levels of prolactin, which remain higher than normal until the frequency and duration of daily suckling decreases and allows normal menstrual function resumption. Hyperprolactinemia induces the suppression of hypothalamic Kiss1 neurons that directly control the pulsatile release of GnRH. Disruption in the pulsatile manner of GnRH secretion results in a strongly decreased frequency of corresponding LH pulses. Inadequate LH secretion and lack of pre-ovulatory surge inhibit the progression of the follicular phase of a menstrual cycle and result in anovulation and amenorrhea. The main consequences of lactational amenorrhea are connected with fertility issues and increased bone turnover. Provided the fulfillment of all the established conditions of its use, the lactational amenorrhea method (LAM) efficiently protects against pregnancy. Because of its accessibility and lack of additional associated costs, LAM might be especially beneficial in low-income, developing countries, where modern contraception is hard to obtain. Breastfeeding alone is not equal to the LAM method, and therefore, it is not enough to successfully protect against conception. That is why LAM promotion should primarily focus on conditions under which its use is safe and effective. More studies on larger study groups should be conducted to determine and confirm the impact of behavioral factors, like suckling parameters, on the LAM efficacy. Lactational bone loss is a physiologic mechanism that enables providing a sufficient amount of calcium to the newborn. Despite the decline in bone mass during breastfeeding, it rebuilds after weaning and is not associated with a postmenopausal decrease in BMD and osteoporosis risk. Therefore, it should be a matter of concern only for lactating women with additional risk factors or with low BMD before pregnancy. The review summarizes the effect that breastfeeding exerts on the hypothalamus-pituitary axis as well as fertility and bone turnover aspects of lactational amenorrhea. We discuss the possibility of the use of lactation as contraception, along with this method's prevalence, efficacy, and influencing factors. We also review the literature on the topic of lactational bone loss: its mechanism, severity, and persistence throughout life.

Goals, life events, and transitions: examining fertility apps for holistic health tracking

OBJECTIVE

Fertility is becoming increasingly supported by consumer health technologies, especially mobile apps that support self-tracking activities. However, it is not clear whether the apps support the variety of goals and life events of those who menstruate, especially during transitions between them.

METHODS

Thirty-one of the most popular fertility apps were evaluated, analyzing data from three sources: the content of app store pages, app features, and user reviews.

FINDINGS

Results suggest that fertility apps are designed to support specific life goals of people who menstruate, offering several data collection features and limited feedback options. However, users often desire holistic tracking that encompasses a variety of goals, life events, and the transitions among them.

DISCUSSION

These findings suggest fertility patients can benefit more from holistic self-tracking and provide insights for future design of consumer health technologies that better support holistic fertility tracking.

CONCLUSION

Fertility apps have the potential to support varied experiences of people who menstruate. But to achieve that, apps need to expand their support by offering ways for more users to perform holistic, personalized, and personally meaningful tracking, so they can derive long-term benefit from the data they collect.

Association Between Breastfeeding and Ovarian Cancer Risk

Importance

Breastfeeding has been associated with a reduced risk of epithelial ovarian cancer in multiple studies, but others showed no association. Whether risk reduction extends beyond that provided by pregnancy alone or differs by histotype is unclear. Furthermore, the observed associations between duration and timing of breastfeeding with ovarian cancer risk have been inconsistent.

Objective

To determine the association between breastfeeding (ie, ever/never, duration, timing) and ovarian cancer risk overall and by histotype.

Design, Setting, and Participants

A pooled analysis of parous women with ovarian cancer and controls from 13 case-control studies participating in the Ovarian Cancer Association Consortium was performed. Odds ratios (ORs) and 95% CIs of the overall association were calculated using multivariable logistic regression and polytomous logistic regression for histotype-specific associations. All data were collected from individual sites from November 1989 to December 2009, and analysis took place from September 2017 to July 2019.

Exposures

Data on breastfeeding history, including duration per child breastfed, age at first and last breastfeeding, and years since last breastfeeding were collected by questionnaire or interview and was harmonized across studies.

Main Outcomes and Measures

Diagnosis of epithelial ovarian cancer.

Results

A total of 9973 women with ovarian cancer (mean [SD] age, 57.4 [11.1] years) and 13 843 controls (mean [SD] age, 56.4 [11.7] years) were included. Breastfeeding was associated with a 24% lower risk of invasive ovarian cancer (odds ratio [OR], 0.76; 95% CI, 0.71-0.80). Independent of parity, ever having breastfed was associated with reduction in risk of all invasive ovarian cancers, particularly high-grade serous and endometrioid cancers. For a single breastfeeding episode, mean breastfeeding duration of 1 to 3 months was associated with 18% lower risk (OR, 0.82; 95% CI, 0.76-0.88), and breastfeeding for 12 or more months was associated with a 34% lower risk (OR, 0.66; 95% CI, 0.58-0.75). More recent breastfeeding was associated with a reduction in risk (OR, 0.56; 95% CI, 0.47-0.66 for <10 years) that persisted for decades (OR, 0.83; 95% CI, 0.77-0.90 for ≥30 years; P for trend = .02).

Conclusions and Relevance

Breastfeeding is associated with a significant decrease in risk of ovarian cancer overall and for the high-grade serous subtype, the most lethal type of ovarian cancer. The findings suggest that breastfeeding is a potentially modifiable factor that may lower risk of ovarian cancer independent of pregnancy alone.

Menstrual bleeding and spotting with the Levonorgestrel Intrauterine System (52 mg) during the first-year after insertion: a systematic review and meta-analysis

BACKGROUND

Changes in menstrual bleeding concern many users of the 52 mg Levonorgestrel Intrauterine System. Prescribing information for Levonorgestrel Intrauterine System devices describe an overall decrease in bleeding and spotting days over time; however, estimates derived from a variety of existing clinical data are currently unavailable.

OBJECTIVE

The objective of the study was to systematically calculate the mean days of bleeding-only, spotting-only, and bleeding and/or spotting experienced by a population of reproductive-aged Levonorgestrel Intrauterine System users with normal regular menses prior to insertion during the first year of use.

DATA SOURCES

We identified clinical trials, including randomized controlled trials and randomized comparative trials, as well as cohort studies published in English between January 1970 and November 2018 through searching 12 biomedical and scientific literature databases including MEDLINE and ClinicalTrials.gov.

STUDY ELIGIBILITY CRITERIA

We considered studies that reported data on Levonorgestrel Intrauterine System devices releasing 20 μg of levonorgestrel per day, collected daily menstrual bleeding data for at least 90 consecutive days, defined bleeding and spotting per World Health Organization standards and evaluated participants with normal regular menses prior to insertion.

STUDY APPRAISAL AND SYNTHESIS METHODS

We assessed study quality using established guidelines. Two reviewers independently conducted all review stages and rated the quality of evidence for each article; any disagreements were resolved by a third. Where possible, we pooled data using a random-effects model.

RESULTS

Among 3403 potentially relevant studies, we included 7 in our meta-analysis. We calculated the mean days of bleeding-only, spotting-only, and bleeding and/or spotting for the first four 90 day intervals after Levonorgestrel Intrauterine System insertion. Combined menstrual bleeding and/or spotting days gradually decreased throughout the first year, from 35.6 days (95% confidence interval, 32.2-39.1) during the first 90 day interval to 19.1 (95% confidence interval, 16.6-21.5), 14.2 (95% confidence interval, 11.7-16.8), and 11.7 days (95% confidence interval, 9.7-13.7) in the second, third, and fourth intervals. Measures for bleeding-only and spotting-only days similarly decreased throughout the first year, with the greatest decreases occurring between the first and second intervals.

CONCLUSION

Our study provides 90 day reference period measures that characterize menstrual patterns for Levonorgestrel Intrauterine System users with normal regular menses prior to insertion during the first year of use. Our findings provide broader generalizability and more detail than patterns described in the prescribing information. These findings quantify an overall decrease in menstrual bleeding days with longer duration of use, with the greatest decrease occurring between months 3 and 6. Accurately establishing expectations with the Levonorgestrel Intrauterine System may improve informed selection and decrease discontinuation.

The role of prolactin in co-ordinating fertility and metabolic adaptations during reproduction

Mammalian pregnancy and lactation is accompanied by a period of infertility that takes place in the midst of a sustained increase in food intake. Indeed, successful reproduction in females is dependent on co-ordination of the distinct systems that regulate reproduction and metabolism. Rather than arising from different mechanisms during pregnancy and lactation, we propose that elevations in lactogenic hormones (predominant among these being prolactin and the placental lactogens), are ideally placed to influence both of these systems at the appropriate time. We review the literature examining the impacts of lactogens on fertility and energy homeostasis in the virgin state, during pregnancy and lactation and potential long-term impacts of reproductive experience. Taken together, the literature indicates that duration and pattern of lactogen exposure is a vital factor in the ability of these hormones to alter reproduction and food intake. Transient increases in prolactin, as typically seen in healthy virgin females and males, are unable to exert lasting impacts. Importantly, both suppression of fertility and increased food intake are only observed following exposure to chronically-elevated levels of lactogens. Physiologically, the only time this pattern of lactogenic secretion is maintained in the healthy female is during pregnancy and lactation, when co-ordination between these regulatory systems emerges. This article is part of the special issue on 'Neuropeptides'.

Levonorgestrel intrauterine system associated amenorrhea: a systematic review and metaanalysis

Objective Data

Amenorrhea is a polarizing noncontraceptive effect of the levonorgestrel intrauterine system. Composite amenorrhea prevalence estimates that summarize all clinical data for the first-year after insertion currently are not available. The purpose of this study was to investigate the validity of existing prevalence estimates by the systematic calculation of amenorrhea measures for a general population of levonorgestrel intrauterine system users and to provide 90-day interval point estimates for the first year of use.

Study

We identified clinical trials, randomized controlled trials, and randomized comparative trials that were published in English between January 1970 and September 2017 through electronic searches of 12 biomedical and scientific literature databases that included MEDLINE and ClinicalTrials.gov.

Study Appraisal and Synthesis Methods

We considered studies that clearly defined amenorrhea per World Health Organization standards (the complete cessation of bleeding for at least 90 days), collected data from written daily bleeding diaries (the gold standard data collection technique on menstrual bleeding changes), and evaluated levonorgestrel intrauterine system devices that released 20 μg of levonorgestrel per day. We assessed study quality using guidelines established by the US Preventive Services Task Force and Cochrane handbook for systematic reviews of interventions. Two reviewers independently conducted all review stages; disagreements were resolved by a third reviewer. Where possible, data were pooled with the use of a random-effects model.

Results

Of 2938 potentially relevant studies, we included 9 in our meta-analysis. We calculated amenorrhea prevalence, which was weighted for inter- and intrastudy variance, for 4 90-day intervals and months 0–12. Our results demonstrated few levonorgestrel intrauterine system users (0.2%; 95% confidence interval, 0.0–0.4) experienced amenorrhea during the first 90 days after insertion; however, prevalence increased to 8.1% (95% confidence interval, 6.6–9.7) on days 91–180. Finally, 18.2% (95% confidence interval, 14.9–21.5) of users experienced amenorrhea for at least 1 90-day interval during the first year. Although interstudy heterogeneity limited reliability of days 181–271 and 272–365 measures, prevalence increased from 13.6% (95% confidence interval, 9.3–18.0) to 20.3% (95% confidence interval, 13.5–27.0), respectively.

Conclusion

Approximately 20% of levonorgestrel intrauterine system users experience amenorrhea during at least 1 90-day interval by the first year after insertion. This composite estimate is consistent with the product labeling and demonstrates that most users do not experience amenorrhea during the first year. These results provide accurate summary measures to facilitate counselling and informed method selection.

Examining Menstrual Tracking to Inform the Design of Personal Informatics Tools

We consider why and how women track their menstrual cycles, examining their experiences to uncover design opportunities and extend the field's understanding of personal informatics tools. To understand menstrual cycle tracking practices, we collected and analyzed data from three sources: 2,000 reviews of popular menstrual tracking apps, a survey of 687 people, and follow-up interviews with 12 survey respondents. We find that women track their menstrual cycle for varied reasons that include remembering and predicting their period as well as informing conversations with healthcare providers. Participants described six methods of tracking their menstrual cycles, including use of technology, awareness of their premenstrual physiological states, and simply remembering. Although women find apps and calendars helpful, these methods are ineffective when predictions of future menstrual cycles are inaccurate. Designs can create feelings of exclusion for gender and sexual minorities. Existing apps also generally fail to consider life stages that women experience, including young adulthood, pregnancy, and menopause. Our findings encourage expanding the field's conceptions of personal informatics.

Late onset postpartum psychoses

It has been known since the eighteenth century that postpartum psychoses can begin several weeks after childbirth, not during the first fortnight. There are almost 400 non-organic episodes in the literature, starting more than 3 weeks after the birth; some of them are recurrent. The distinction of this disorder from early onset puerperal psychosis is supported by the distribution of onsets (which shows a steep fall after 14-15 days), survey data and the association with later pregnancies, not the first. Marcé believed that these late onsets were related to the resumption of menstruation. This is a hypothesis worth investigating.

Postpartum Sexuality and the Lactational Amenorrhea Method for Contraception

This chapter reviews the literature on postpartum coital behavior, anovulatory and ovulatory bleeding episodes, and the methodology and efficacy of Lactational Amenorrhea Method and progesterone-only oral contraceptives. Of interest is the finding that breastfeeding women may resume coital behavior earlier postpartum, but report increased discomfort over time. The high efficacy of the Lactational Amenorrhea Method is confirmed and data illustrating possible relaxation of some criteria are presented. The conflicting guidance of CDC and WHO concerning immediate postpartum use of progestin-only methods is presented. The dearth of recent studies calls for new research on these topics.

Postpartum contraception

As birth spacing has demonstrated health benefits for a woman and her children, contraception after childbirth is recognized as an important health issue. The potential risk of pregnancy soon after delivery underscores the importance of initiating postpartum contraception in a timely manner. The contraceptive method initiated in the postpartum period depends upon a number of factors including medical history, anatomic and hormonal factors, patient preference, and whether or not the woman is breastfeeding. When electing a contraceptive method, informed choice is paramount. The availability of long-acting reversible contraceptive methods immediately postpartum provides a strategy to achieve reductions in unintended pregnancy.

ABM Clinical Protocol #13: Contraception During Breastfeeding, Revised 2015

A central goal of The Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient.

Prospective study of birth interval dynamics in rural Bangladesh

Abstract A group of 209 married, fecund women in rural Bangladesh were studied prospectively for 24 months from 1969 to 1971 to define some of the biological and sociological factors relating to fertility performance. These women were selected from a larger study population of 112,000 that had been followed with a daily house-to-house vital registration programme since 1966. The selected women were interviewed bi-weekly and were asked questions about menstruation, pregnancy, lactation, husband's occupational absences, and monthly urine tests for pregnancy were taken. The results for 193 non-contracepting women revealed that the seasonal pattern of births previously observed in this population could be associated with a corresponding seasonal pattern of conceptions and that this was due to a seasonal trend in fecundability. The highest conception rates were in the coolest months of the year. Post-partum lactational amenorrhoea was very prolonged, averaging 17 months for women with a surviving child. The appearance of the first post-partum menstrual flow (onset of ovulation) also had a seasonal trend which could not be adequately explained. The median waiting time to conception, once menstruation had resumed was eight months. This interval was influenced by seasonal fluctuations, as well as by the age of women and by husbands' absences. The foetal wastage rate was 15·0 per 100 conceptions, with 62 per cent of the foetal losses occurring during the second month of gestation. Overall, the average birth interval was 33 months, with the prolonged lactational amenorrhoea accounting for almost 45 per cent of this interval. From the Department of Population Dynamics, Johns Hopkins University, School of Hygiene and Public Health, Baltimore, Maryland 21205.

Return of ovulation and menses in postpartum nonlactating women: a systematic review

OBJECTIVES

To estimate, from the literature, when nonlactating postpartum women regain fertility.

DATA SOURCES

We searched PubMed and Cochrane Library databases for all articles (in all languages) published in peer-reviewed journals from database inception through May 2010 for evidence related to the return of ovulation and menses in nonlactating postpartum women. Search terms included "Fertility" (Mesh) OR "Ovulation" (Mesh) OR "Ovulation Detection" (Mesh) OR "Ovulation Prediction" (Mesh) OR fertility OR ovulat* AND "Postpartum Period" (Mesh) OR postpartum OR puerperium AND Human AND Female.

METHODS OF STUDY SELECTION

We included articles assessing nonlactating women's first ovulation postpartum. Studies in which women breastfed for any period of time or in whom lactation was suppressed with medications were excluded.

TABULATION, INTEGRATION AND RESULTS

We identified 1,623 articles; six articles reported four studies met our inclusion criteria. In three studies utilizing urinary pregnanediol levels to measure ovulation, mean day of first ovulation ranged from 45 to 94 days postpartum; 20%-71% of first menses were preceded by ovulation and 0%-60% of these ovulations were potentially fertile. In one study that used basal body temperature to measure ovulation, mean first ovulation occurred on day 74 postpartum; 33% of first menses were preceded by ovulation and 70% of these were potentially fertile.

CONCLUSION

Most nonlactating women will not ovulate until 6 weeks postpartum. A small number of women will ovulate earlier, potentially putting them at risk for pregnancy sooner, although the fertility of these early ovulations is not well-established. The potential risk of pregnancy soon after delivery underscores the importance of initiating postpartum contraception in a timely fashion.

Health effects of breast feeding for mothers: a critical review

Lactation results in a number of physiological adaptations which exert direct effects on maternal health, some of which may confer both short and long term advantages for breast feeding mothers. Breast feeding in the early postpartum period promotes a more rapid return of the uterus to its prepregnant state through the actions of oxytocin. Breast feeding may also lead to a more rapid return to prepregnancy weight. Among studies that had good data on duration and intensity of lactation, the majority show a significant association between lactation and weight loss. However, there is no evidence that lactation prevents obesity. Lactation also affects glucose and lipid metabolism. The long term effects of these adaptations are unknown but may have implications for preventing subsequent development of diabetes and heart disease. Lactation delays the return of ovulation and significantly reduces fertility during the period of lactational amenorrhoea. This process is linked with feeding patterns and may therefore be affected by practices such as scheduled feedings and the timing of introduction of complementary foods. While the evidence from epidemiologic studies is mixed, several large studies have shown that extended lactation is associated with reduced risk of premenopausal breast, ovarian and endometrial cancers. Although bone mineralization declines during lactation, repletion takes place after weaning. As a result, breast feeding does not appear to cause long term depletion of bone nor does it increase risk of osteoporosis. Many of the physiological effects of lactation are dependent on the stimulation of the hypothalamic-pituitary axis and milk removal and thus may vary with infant feeding practices. Well controlled studies are needed that include detailed information regarding infant feeding practices in addition to the total duration of any breast feeding. Future feeding recommendations should reflect careful consideration of how such practices affect both infant and maternal health.

Significance of the secretion of human prolactin and gonadotropin for puerperal lactational infertility

The causes of puerperal infertility in lactating women are poorly understood. The controlling centres may be either the hypothalamic-pituitary axis or the ovary (or both). We studied the secretory dynamics of prolactin and gonadotropins in healthy, normal, lactating and non-lactating women after administering either gonadoliberin to assess pituitary responsiveness or human menopausal gonadotropins to assess ovarian responsiveness during the puerperium. A reciprocal relationship was observed between the secretion of gonadotropins and the secretion of prolactin after the nipples of mothers who were breast-feeding had been stimulated for 30 min. The absence of a short-loop negative feedback control by prolactin for gonadotropin secretion was not confirmed because cyclic secretion of gonadotropin was not necessarily impaired by hyperprolactinaemia. Hyperprolactinaemia did, however, appear to impair the function of the corpus luteum in women suffering from non-puerperal galactorrhoea. We postulate a multifactorial mechanism for puerperal infertility based initially on the peripheral concentration of prolactin and gonadotropins and, in some poorly defined way, on the cerebral concentration of catecholamines.

ABM clinical protocol #13: contraception during breastfeeding

A central goal of the Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may influence breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient.

Endocrine factors in the etiology of postpartum depression

This article reviews the literature regarding endocrine factors postulated or presumed to be relevant in postpartum depression (PPD), a condition affecting at least 10% of childbearing women. The phenomenology and epidemiology of PPD are also described. Data suggest that parturition-related endocrine changes are causally implicated in PPD in a vulnerable subgroup of women. More specifically, studies by our group and others suggest a role for changes in estradiol and progesterone in precipitating mood symptoms among women with PPD. The mechanisms underlying such differential sensitivities remain undetermined. Future directions for research are explored.

Life-history theory, fertility and reproductive success in humans

According to life-history theory, any organism that maximizes fitness will face a trade-off between female fertility and offspring survivorship. This trade-off has been demonstrated in a variety of species, but explicit tests in humans have found a positive linear relationship between fitness and fertility. The failure to demonstrate a maximum beyond which additional births cease to enhance fitness is potentially at odds with the view that human fertility behaviour is currently adaptive. Here we report, to our knowledge, the first clear evidence for the predicted nonlinear relationship between female fertility and reproductive success in a human population, the Dogon of Mali, West Africa. The predicted maximum reproductive success of 4.1+/-0.3 surviving offspring was attained at a fertility of 10.5 births. Eighty-three per cent of the women achieved a lifetime fertility level (7-13 births) for which the predicted mean reproductive success was within the confidence limits (3.4 to 4.8) for reproductive success at the optimal fertility level. Child mortality, rather than fertility, was the primary determinant of fitness. Since the Dogon people are farmers, our results do not support the assumptions that: (i) contemporary foragers behave more adaptively than agriculturalists, and (ii) that adaptive fertility behaviour ceased with the Neolithic revolution some 9000 years ago. We also present a new method that avoids common biases in measures of reproductive success.

Effects of breastfeeding on the mother

In the rush to find nutrient alternatives to breastfeeding, a theme that dominated research on infant feeding throughout the twentieth century, only recently have new findings that reconfirm the importance of breastfeeding for maternal and child health begun to influence medical texts and health policy. Approximately 30 years of increasingly rigorous and positive research findings have led to the rediscovery of breastfeeding as a valid and evidence-based health intervention for infants. Unfortunately, because much of the research was designed to assess human milk as a nutrient replacement for infant formula, the literature on the effects of breastfeeding on maternal health remain limited. Nonetheless, a clear pattern of positive physiologic changes that lead to improved short-term and long-term health sequelae are emerging. All patients and their families should be informed fully as to the positive preventive health effects of breastfeeding not only for infants but also for mothers. Women have many difficult choices to make; it behooves physicians to ensure that they receive all of the facts on which to base these decisions.

Predictors of fecundability and conception waits among the Dogon of Mali

Surprisingly little is known about the mechanisms that underlie variation in female fertility in humans. Data on this topic are nonetheless vital to a number of pragmatic and theoretical enterprises, including population planning, infertility treatment and prevention, and evolutionary ecology. Here we study female fertility by focusing on one component of the interbirth interval: the waiting time to conception during menstrual cycling. Our study population is a Dogon village of 460 people in Mali, West Africa. This population is pronatalist and noncontracepting. In accordance with animist beliefs, the women spend five nights sleeping at a menstrual hut during menses. By censusing the women present at the menstrual huts in the study village on each of 736 consecutive nights, we were able to monitor women's conception waits prospectively. Hormonal profiles confirm the accuracy of the data on conception waits obtained from the menstrual hut census (Strassmann [1996], Behavioral Ecology 7:304-315). Using survival analysis, we identified significant predictors of the waiting time to conception: wife's age (years), husband's age (< 35, 35-49, > 49 years), marital duration (years), gravidity (number of prior pregnancies), and breast-feeding status. Additional variables were not significant, including duration of postpartum amenorrhea, sex of the last child, nutritional status, economic status, polygyny, and marital status (fiancée vs. married). We fit both continuous and discrete time survival models, but the former appeared to be a better choice for these data.

Documentation of second-by-second breastfeeding behaviors using a novel method

The specific way nursing patterns influence the duration of postpartum amenorrhea is unknown. This may result from the shortcomings of available methods: the daily log and recall. We tested these against a novel method, an event monitor (EM), consisting of a wrist-worn stopwatch that stores events. Exclusively breastfeeding women (n = 11) were assigned randomly to use each of the three methods twice during a 2-week period surrounding Weeks 4, 8, and 12 postpartum. More nursing episodes were recorded with the EM than log during Week 4 (p < 0.03) and Week 8 (p < 0.02). EM captured more episodes than recall during all study periods (p < 0.004). The EM was considered as acceptable and accurate to mothers as the other methods and, therefore, is a useful option for documenting breastfeeding patterns.

Recovery of ovarian function after childbirth, lactation and sexual activity with relation to age of women

The time for recovery of ovulation, lactation and initiation of sexual intercourse after childbirth was studied in 90 women, who were divided into three groups: 1) adolescents less than 19 years old (n = 30); 2) younger mothers 19 to 32 years old (n = 30); and 3) older women more than 32 years old (n = 30). No differences were found in the duration of breast-feeding or in the initiation of sexual intercourse among the three groups. The postpartum amenorrhea in lactating women was significantly longer than in nonlactating mothers. The amenorrhea was significantly less in younger women than in older mothers and tended to be lower than in adolescents. The time between delivery and detection of ovulation was significantly longer in women who breast-fed than in those who did not. Furthermore, this time was significantly shorter in younger women than in older mothers. The present work suggests that younger women had a quicker recovery of ovarian function than adolescents and older women.

Market penetration of new drugs. ACE inhibitors prescribed for heart failure

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Market penetration of new drugs. Compare Britain with other national markets

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Postpartum contraception. Unnecessary before three weeks

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Market penetration of new drugs. Increased prescribing may be appropriate

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The return of postpartum fertility monitored by enzyme-immunoassay for salivary progesterone

A longitudinal study in which daily salivary progesterone and estrone were measured by solid-phase enzyme-immunoassays was performed in 30 postpartum women to monitor the return of ovarian activity. Ovulation was inferred from a sustained rise in salivary progesterone over 251 pmol/l, but salivary estrone measurements were not as informative as progesterone in this regard. Recovery of ovarian activity was slower in lactating women compared with non-lactators; the mean delivery-menstruation interval were 123 (+/- 10) and 57 (+/- 7) days, respectively. An abnormal luteal phase was noted in 35% of the first ovulatory cycles, 20% had short luteal phases and 15% were less than the 5th percentile of a normal control corridor. The pregnancy rate in this study of 3.3% was lower than the anticipated rate of 8.8%. We conclude that salivary progesterone measurements are useful for monitoring the return of ovarian activity postnatally.

Is the lactational amenorrhea method a part of natural family planning? Biology and policy

The lactational amenorrhea method is a natural method of family planning for women who breastfeed their infants. The underlying physiology results in a natural suppression of ovulation, and the concomitant amenorrhea, induced by exclusive (or almost exclusive) breastfeeding. This in addition to the infant's age of 6 months or less and specific feeding pattern are the parameters used to identify the possible return of fertility. The lactational amenorrhea method provides at least 98% protection against pregnancy. Data from a recent multicenter study of breastfeeding support the use of the lactational amenorrhea method as a natural family planning method. The lactational amenorrhea method can be incorporated into natural family planning programs and teaching.

Breastfeeding and return to ovulation in Bangkok

Twenty-seven breastfeeding mothers and nine non-breastfeeding postpartum comparison mothers in Bangkok, Thailand were followed longitudinally until ovulation resumed. A simple set of guidelines is described involving three obvious milestones for the breastfeeding mother to safely use the natural contraceptive benefit of breastfeeding. Those milestones are the first menses, the initiation of supplementation and the child's monthly birthday. In the absence of menses and supplementation, 93% of breastfeeding mothers remained anovular for 3 months postpartum and 88-89% for up to 6 months. Further, the work of other investigators suggests that the proportion ovulatory provides an overestimate of those at risk of pregnancy. The guidelines suggest a way to estimate the period of lactational infertility and may be most useful on a programmatic level.

Mini-pill in lactating women

A non-comparative study of the progestogen-only oral contraceptive, norgestrel 0.075 mg, in breast-feeding women was conducted at the Centro de Investigaciones Regionales, Merida, Yucatan, Mexico. The study was designed to evaluate the overall acceptability and contraceptive efficacy of norgestrel in breast-feeding women. This report includes a survey of 200 women, all of whom were less than 26 weeks postpartum at admission; 113 were interval patients and 87 were postpartum. Follow-up visits were scheduled at 2, 6 and 12 months after admission. Overall, women experienced an increase in intermenstrual bleeding, amenorrhea, vaginal discharge and breast discomfort. The discontinuation rate at 12 months was 32.5 and the corresponding lost to follow-up rate was 22.5; this is a measure of acceptability. The 12-month life-table rate for pregnancy was 3.4 with a standard error of 2.0. Three women discontinued use of the mini-pill due to accidental pregnancy. One pregnancy was attributed to user failure and the woman conceived 9 months after entering into the study; the other two were attributed to method failure, one woman conceived 3 months after admission and the other conceived 6 months after admission.

Consensus statement on the use of breastfeeding as a family planning method

An interdisciplinary international group of researchers in the area of lactational infertility gathered with the purpose of coming to a consensus about the conditions under which breastfeeding can be used as a safe and effective method of family planning. The consensus of the group was that the maximum birth spacing effect of breastfeeding is achieved when a mother "fully" or nearly fully breastfeeds and remains amenorrheic. When these two conditions are fulfilled, breastfeeding provides more than 98% protection from pregnancy in the first six months. Data are reviewed from thirteen prospective studies in both developed and developing countries supporting the consensus. The rationale for the consensus is given in detail. Recommendations are made based on what is currently known of the antifertility effects of breastfeeding. Research should continue to measure a broad spectrum of variables so that these guidelines can be refined as new information becomes available.

Breast-feeding and post-partum amenorrhoea in Indonesia

The association between breast-feeding patterns and resumption of menses post-partum was examined in a prospective study in Indonesia. In order to examine these relationships directly in a longitudinal study, it was first necessary to distinguish among women who experienced infant mortality before menses resumed, women who weaned before menses resumed, and women who had return to menses while breast-feeding. Information on suckling patterns and menstrual status was collected by recall for 444 women at monthly visits for 2 years. Three main breast-feeding variables, minutes per episode, number of episodes per day, number of episodes per night, and other breast-feeding variables were derived for each woman, to give the average nursing pattern up to menses or the end of the study, which-ever came first. While high levels of nursing for each of these three main variables were found to be significantly related to delay in return of menses post-partum, the interactions between more minutes per episode, and more frequent day- and night-time feeds, were found to be the most important factors in the delay in onset of post-partum menstruation in those women whose menses resumed while still nursing or who remained amenorrhoeic and nursing at the end of the study.

The use of breastfeeding as a contraceptive

Breastfeeding generally is considered an ineffective method of birth control. Yet, in non-Western cultures breastfeeding has been shown to be a beneficial method for spacing births. The physiological effect of breastfeeding on ovulation, breastfeeding patterns that delay the return of ovulatory activity, and the practice of fertility awareness during the postpartum period are reviewed. Guidelines are suggested for assessing, teaching, and referring women desiring to use breastfeeding as a contraceptive method.

Ecological breastfeeding and child spacing

Until the 2nd and 3rd decades of this century, breastfeeding was essential for infant survival. In that period, spacing of children was generally about 2 years. Later, improved modified cow's milk preparations became commercially available and were well tolerated by most infants. As a result, near cessation of ecological breastfeeding occurred toward the middle of the century. The decline in ecological breastfeeding was associated with early postpartum ovulation and shortened child-spacing of about 1 year. The endocrinology of breastfeeding is now known in considerable detail. Prolactin is secreted promptly in response to nipple stimulation and is a reliable marker of the endocrine alterations occurring postpartum. Success of lactation in suppression of ovulation was found to occur when infants sucked frequently and when only small amounts of selected foods were introduced gradually after the infants were about 6 months of age.

The recovery of ovarian function during breast-feeding

The pattern of breast-feeding was daily recorded and the serum concentrations of prolactin (PRL), FSH, LH, estradiol (E2) and progesterone (prog) were measured at weekly intervals in 26 breast-feeding mothers from the time of delivery and up to the resumption of regular ovulation or to the end of the first postpartum year. Twelve postpartum non-breast-feeding women were similarly studied as controls. An algorithm was used to characterize ovulatory events into three types: the first, with evidence highly suggestive of normal ovulation (EHSO), the second, with evidence of probable ovulation (EPO) and the third with evidence indicating questionable ovulation or deficient corpus luteum function (QO/DCT). Pregnancy preceded the first menstruation in one woman in each of the breast-feeding and control groups. Of the 19 breast-feeding women who started to menstruate during the first postpartum year, five had EHSO, one had EPO, 5 had EQO/DCL and 7 had anovulatory (AO) menstruation. The corresponding figures in the 11 controls were 6, 2, 3 and 0. Pregnancy occurred before a second menstruation in one woman in both the study group and the controls. In 18 breast-feeding women observed, the second menstruation was preceded by EHSO in 7, by EPO in 3, by EQO/DCL in one and AO in 7. In 10 controls the corresponding figures were 7, 3, 0 and 0. Out of a total of 79 menstruations observed during breast-feeding the incidence of AO was 30% and of QO/DCL was 15%. In actively breast-feeding mothers, hyperprolactinemia persisted for more than 1 yr. However, menstruation and ovulation occasionally occurred before the drop of PRL to concentrations seen during the normal menstrual cycle. In the majority of women, low E2 levels were present during lactational amenorrhea, but with occasional spikes in some. A few women maintained somewhat high values of E2 for several weeks before the resumption of menstruation. The implications of these hormonal findings to the attempts to improve on the contraceptive effect of breast-feeding are discussed.

Breastfeeding: its relationship with postpartum amenorrhea and postpartum sexual abstinence in a Nigerian community

Breastfeeding, together with its two related postpartum variables--amenorrhea and abstinence--govern both the tempo and quantum of fertility in traditional African societies. Decline in breastfeeding also implies decline in postpartum amenorrhea and abstinence practice. Changes in breastfeeding practices in tropical Africa, therefore, has fertility implications and consequences. This paper examines how breastfeeding is functionally related to postpartum amenorrhea and abstinence in Ilorin, an urban community in Nigeria. Results indicated that the effect of breastfeeding on fertility, through its relationship with postpartum abstinence, might be more important than its effect through lactational amenorrhea in this society. This is more true among women with little or no education than among women with secondary or higher education. The population or family planning implications of these relationships are discussed.

Exercise reduces gonadal atrophy caused by short photoperiod or blinding of hamsters

The effect of voluntary exercise upon several reproductive parameters was assessed in male Syrian hamsters. Forty-two animals were caged in five groups and then blinded: Ten housed five per plastic cage; eight housed individually in plastic cages; six housed individually in plastic cages with 15 cm exercise wheels in the cage; eight housed in Wahmann steel activity cages with 36 cm wheels locked to prevent rotation; ten housed in functional Wahmann running wheel cages. At 16 weeks after blinding, animals with access to functional running wheels had significantly larger testes (3.7 +/- 1.0 g) than those with no wheels or locked wheels (1.86 +/- 0.6 g; mean +/- SD; p less than 0.001). These results suggested that voluntary exercise reduces testicular atrophy caused by blinding. A second experiment was run in which the animals were subjected to a short photoperiod (LD 6:18) for 12 weeks instead of blinding. Similar results were obtained except that access to the small exercise wheels did not affect testicular atrophy: Mean testicular mass of animals in individual cages = 0.79 +/- 0.3 g, small wheels = 0.74 +/- 0.4 g, functional Wahmann wheels, 2.56 +/- 1.0 g, locked Wahmann wheels 0.52 +/- 0.1 g (p less than 0.01).

Contraception during lactation: considerations in advising the individual and in formulating programme guidelines

Lactating women are at reduced risk of conception, but the individual woman may not wish to accept even a reduced level of risk. The risk increases when infant feeding supplementation begins and an alternative form of contraception is then required for the lactating mother. The relationship between lactation and fertility, trends in prolonged lactation, factors affecting these trends, and contraceptive use during lactation are reviewed. Suggestions for advising individuals and formulating programme guidelines are discussed.

Preliminary observations on the return of ovarian function among breast-feeding and post-partum non-breast-feeding women in a rural area of Mexico

The relationship between the return of menstruation and ovulation and the pattern of breast-feeding was studied in a group of 29 women in a rural area of Mexico; eight non-breast-feeding post-partum women were also studied. The return of ovulation was assessed by weekly determinations of urinary pregnanediol. The number of suckling episodes and supplementary feeds was recorded. The cumulative probability of resumption of menses for the breast-feeders was 28% and 52% at 3 and 6 months, respectively, and for the non-breast-feeders was 75% and 88%. The cumulative probability of ovulation for the breast-feeders was 28%, 66%, 69% and 72% at 3, 6, 9 and 12 months, respectively, and for the non-breast-feeders was 50% and 100% at 3 and 6 months. The earlier the introduction of supplements the earlier the return of ovulation. The nonovulatory subjects maintained a higher frequency of suckling episodes than did the ovulatory subjects. The cumulative probability of pregnancy for the breast-feeders was 3%, 7%, 7% and 10% at 3, 6, 9 and 12 months, respectively, and for the non-breast-feeders was 13%, 38% and 50% at 3, 6 and 9 months.

Prolactin and the return of ovulation in breast-feeding women

Cross-sectional studies in Australia and the Philippines and a longitudinal prospective study in a selected Australian sample of breast-feeding mothers have shown that basal serum prolactin (PRL) concentrations are elevated during 15–21 months of lactational amenorrhoea.

A predictive model of serum PRL levels and return of cyclic ovarian activity during full breast-feeding, partial breast-feeding and weaning has been developed from the results of breast-feeding behaviour and serum PRL, gonadotrophin and oestradiol measurements in 34 mothers breast-feeding on demand for a mean of 67 weeks.

Breast-feeding patterns influence serum PRL levels. Important factors during full breast-feeding are the age of the baby, the longest interval between feeds at night and total 24-hr suckling time, and following the introduction of supplements, the mean interval between feeds, together with the total 24-hr suckling time and the number of solid supplements per day.

The precise mechanisms whereby breast-feeding regulates cyclic ovarian activity remain unknown. Gonadotrophin secretion appears to be quantitatively normal, but qualitative changes, secondary to altered hypothalamic activity, may be the most important factor. A direct inhibitory effect of PRL on ovarian follicular development and steroidogenesis remains possible.

Ovulation with a normal luteal phase is probable for 30% of breast-feeding mothers before the first menses, but is unlikely before 6 months, provided breast-feeding is frequent day and night.

Measurement of serum PRL is a sensitive index of the return of menstruation and fertility during lactation in the population studied.

The acceptability of a progestagen-only contraceptive during breast-feeding

The acceptability of an oral contraceptive containing norethisterone 0.35 mg was investigated in a group of mothers followed-up at 6 months post-partum. Eighty-four mothers out of a total of 203 (41%) had used this preparation while breast-feeding and 37 (44%) of these were still taking it at the time of follow-up. The most frequent reason for discontinuation was cessation of breast-feeding. The overall duration of breast-feeding did not appear to differ between this group and a group using occlusive methods of contraception. Uterine bleeding during therapy was related to duration of breast-feeding, with 68% of women who breast-fed for longer than five months remaining amenorrhoeic. Irregular bleeding occurred in 12% of the women who breast-fed for longer than 5 months compared with 43% of those who stopped breast-feeding within the first 3 months. In only 9% of cases was the pill discontinued because of side effects, including irregular bleeding.

Fertility after childbirth: infant feeding patterns, basal PRL levels and post-partum ovulation

The infant feeding patterns at the time of first ovulation after childbirth were determined in a longitudinal study of twenty-seven mothers who chose to breast feed their babies. Fourteen mothers suppressed ovulation throughout lactation and thirteen ovulated while still breast feeding. Those who ovulated while breast feeding had all introduced two or more supplementary feeds/day, reduced suckling frequency to less than six times/day and reduced suckling duration to less than 60 min/day at the time of first ovulation. Basal PRL levels had fallen to below 600 microunits/l in all but one of the mothers at first ovulation. Those mothers who suppressed ovulation for more than 40 weeks post-partum (late ovulation group) were compared with those who ovulated between 30 and 40 weeks post-partum (middle group) and with those who ovulated before 30 weeks post-partum (early group). The late ovulation group breast-fed for longest, suckled most intensively, maintained night feeds for longest and introduced supplementary feeds most gradually. This study suggests suckling may be the most important factor inhibiting the return of ovulation during lactation and that policies which encourage increased suckling frequency and duration will maximize the contraceptive effects of breast feeding.